Tree growth in boreal forests is limited by nitrogen (N) availability. Most boreal forest trees form symbiotic associations with ectomycorrhizal (ECM) fungi, which improve the uptake of inorganic N ...and also have the capacity to decompose soil organic matter (SOM) and to mobilize organic N (‘ECM decomposition’).
To study the effects of ‘ECM decomposition’ on ecosystem carbon (C) and N balances, we performed a sensitivity analysis on a model of C and N flows between plants, SOM, saprotrophs, ECM fungi, and inorganic N stores.
The analysis indicates that C and N balances were sensitive to model parameters regulating ECM biomass and decomposition. Under low N availability, the optimal C allocation to ECM fungi, above which the symbiosis switches from mutualism to parasitism, increases with increasing relative involvement of ECM fungi in SOM decomposition. Under low N conditions, increased ECM organic N mining promotes tree growth but decreases soil C storage, leading to a negative correlation between C stores above- and below-ground.
The interplay between plant production and soil C storage is sensitive to the partitioning of decomposition between ECM fungi and saprotrophs. Better understanding of interactions between functional guilds of soil fungi may significantly improve predictions of ecosystem responses to environmental change.
Carbon (C) and nitrogen (N) interact strongly during decomposition of litters with repercussions for stoichiometry of soil organic matter (SOM). A characteristic parameter describing this interaction ...is the critical N:C ratio, rc, i.e. the litter N:C ratio at which net N mineralisation commences. We show here how rc can be estimated from time series of decomposition and use four large data bases to investigate how environment and litter properties determine rc. We find that rc increases with increasing initial litter N:C and N fertilisation. The critical N:C responds also to large scale variations in environment but it is not clear which environmental variable drives this variability. With increasing rc we find an increase in SOM N:C. SOM N:C increases more rapidly than rc, which can be explained if the decrease in substrate quality during decomposition is taken into account.
•The relations between N and C during decomposition of litters were investigated.•Four large data sets with 36 litter types and 16,510 observations were used.•The critical N:C ratio is a stable predictor of litter stoichiometry.•The critical N:C increases with increasing initial litter N:C and N fertilisation.
Background
Short‐term dermoscopic monitoring (STDM) of atypical melanocytic lesions (AML) after 3.0–4.5 months can be used to detect featureless melanomas without performing countless unnecessary ...excisions of nevi. Recently, short‐term teledermoscopic monitoring (STTM) was incorporated into the STDM clinical routine at Sahlgrenska University Hospital in Gothenburg, Sweden. Follow‐up images for STTM were taken by an assistant nurse with subsequent teledermoscopic assessment by a dermatologist.
Objectives
The purpose of this study was to evaluate the diagnostic accuracy and safety of STTM.
Methods
In this retrospective observational study, data from electronic health records of patients with teledermoscopically monitored AMLs were explored. The number of changed and excised AMLs and their histopathological diagnoses were recorded. The excised AMLs were categorized into three subgroups according to when they changed and were excised: (i) following STTM, (ii) after planned long‐term follow‐up or (iii) after unplanned long‐term follow‐up.
Results
A total of 686 patients with 883 AMLs were monitored with STTM. Sixty‐two AMLs (7.0%) were excised following STTM, 14 (1.6%) after planned long‐term follow‐up and 10 (1,1%) after unplanned long‐term follow‐up. Twenty‐one melanomas were detected using STTM, three after planned long‐term follow‐up and three after unplanned long‐term follow‐up. All melanomas were in situ (n = 20) or thin and non‐ulcerated (n = 7; median Breslow thickness 0.4 mm, range 0.3–0.8 mm). The sensitivity for the diagnosis of melanoma by means of STTM with the option of additional planned follow‐up was 88.9%, and the specificity was 93.9%. The number of AMLs needed to monitor in order to detect one melanoma with the STTM routine was 32.7, and the number needed to excise was 3.2.
Conclusions
STTM of AMLs was safe and allowed for high diagnostic accuracy. All detected melanomas were in situ or thin and non‐ulcerated. Furthermore, a considerable number of unnecessary excisions were spared.
The decomposition rate of litter mixtures can differ from that expected on the basis of the decomposition rate of the individual components. This difference may be linked to nitrogen (N) transfer ...from high-N to low-N components. Transfer of N is probably also associated with transfer of C, but the extent and direction of this C transfer are unknown. This study examined transfer and loss in laboratory microcosms of C and N from two mixed litter species (Scots pine, Pinus sylvestris L. and maize, Zea mays L.), which have natural isotopic differences in 13C. Half the material was 15N-labelled and the plants were fertilised or unfertilised. Substantial bidirectional transfer of C and N occurred between the litters, with net transfer of C from pine to maize litter and net transfer of N from high-N to low-N litter. Mixtures of fertilised and unfertilised plant litter showed higher than expected C losses and net transfer of N. Mixtures with litters from the same fertilisation treatment had small or insignificant net transfer of N and their C losses did not differ from values estimated using the decomposition rates of the pure litters.
► We followed the transfer and loss of C and N in mixtures of two litters. ► We found a substantial bidirectional transfer of both C and N between the litters. ► A higher than expected C loss was coupled to a net transfer of N.
Umbilical cord blood (UCB), previously seen as medical waste, is increasingly recognized as a valuable source of cells for therapeutic use. The best-known application is in hematopoietic stem cell ...transplantation (HSCT), where UCB has become an increasingly important graft source in the 28 years since the first umbilical cord blood transplantation (UCBT) was performed. Recently, UCB has been increasingly investigated as a putative source for adoptive cell therapy. Areas covered: This review covers the advances in umbilical cord blood transplantation (UCBT) to overcome the limitation regarding cellular dose, immunological naivety and additional cell doses such as DLI. It also provides an overview regarding the progress in adoptive cellular therapy using UCB. Expert opinion: UCB has been established as an important source of stem cells for HSCT. Successful strategies to overcome the limitations of UCBT, such as the limited cell numbers and naivety of the cells, are being developed, including novel methods to perform in vitro expansion of progenitor cells, and to improve their homing to the bone marrow. Promising early clinical trials of adoptive therapies with UCB cells, including non-immunological cells, are currently performed for viral infections, malignant diseases and in regenerative medicine.
Background
Basal cell carcinoma (BCC) is the most common cancer in the world and has a rising incidence. Current guidelines for low‐risk BCC including superficial BCC (sBCC) recommend several ...treatment options including destructive treatment methods, such as cryosurgery with or without prior curettage or curettage and electrodesiccation. Curettage only (i.e. without subsequent cryosurgery or electrodesiccation) is a simple and quick destructive treatment method used for many benign skin lesions but has not been sufficiently evaluated for the treatment of sBCCs.
Objectives
The objective was to compare the effectiveness of curettage vs. cryosurgery for sBCCs in terms of overall clinical clearance rates after 1 year as well as wound healing times.
Methods
A single‐centre non‐inferiority clinical trial was conducted. Non‐facial sBCCs with a diameter of 5–20 mm were randomised to either cryosurgery using one freeze–thaw cycle or curettage. At follow‐up visits, treatment areas were evaluated regarding the presence of residual tumour after 3–6 months and recurrence after 1 year. Further, wound healing times were assessed.
Results
In total, 228 sBCCs in 97 patients were included in the analysis. At 3–6 months, no residual tumours were seen in any of the treated areas. After 1 year, the clinical clearance rates for curettage and cryosurgery were 95.7% and 100%, respectively (P = 0.060). However, the non‐inferiority analysis was inconclusive. Wound healing times were shorter for curettage (4 weeks) compared to cryosurgery (5 weeks; P < 0.0001). Overall, patient satisfaction at 1 year was high.
Conclusions
Both treatment methods showed high clinical clearance rates after 1 year, whilst curettage reduced the wound healing time.
Background. Viral infections are major complications after allogeneic hematopoietic stem cell transplantation (HSCT). During posttransplant immunosuppression the regular T-cell control is ...compromised. Even if treatment strategies against infections caused by herpes viruses such as cytomegalovirus, Epstein-Barr virus, and adenovirus have improved, the mortality rate is still considerable. If primary antiviral therapy fails or cannot be tolerated, adoptive therapy with virus-specific cytotoxic T cells (CTL) can be utilized. Methods. In this study, we used virus-specific CTLs to treat 8 patients suffering from severe viral infections after allogeneic HSCT. Using positive selection with HLA multimers and magnetic beads, we isolated CTLs from both frozen donor material as well as third-party donors within hours. Results. At 90 days after CTL infusions 7 out of 8 patients were still living. CTLs infused from third-party donors were detected in 5 of 6 patients up to 76 days after infusion. No graft-versus-host disease associated with CTL infusions was observed. Conclusions. Our separation approach offers a rapid alternative for adoptive CTL therapy if primary antiviral treatment strategies fail. Because no prolonged expansion steps are needed, this method may be used for early treatment of patients suffering from life-threatening infectious complications.
Objective To describe possible causes of delivery‐related severe asphyxia due to malpractice.
Design and setting A nationwide descriptive study in Sweden.
Population All women asking for financial ...compensation because of suspected medical malpractice in connection with childbirth during 1990–2005.
Method We included infants with a gestational age of ≥33 completed gestational weeks, a planned vaginal onset of delivery, reactive cardiotocography at admission for labour and severe asphyxia‐related outcomes presumably due to malpractice. As asphyxia‐related outcomes, we included cases of neonatal death and infants with diagnosed encephalopathy before the age of 28 days.
Main outcome measure Severe asphyxia due to malpractice during labour.
Results A total of 472 case records were scrutinised. One hundred and seventy‐seven infants were considered to suffer from severe asphyxia due to malpractice around labour. The most common events of malpractice in connection with delivery were neglecting to supervise fetal wellbeing in 173 cases (98%), neglecting signs of fetal asphyxia in 126 cases (71%), including incautious use of oxytocin in 126 cases (71%) and choosing a nonoptimal mode of delivery in 92 cases (52%).
Conclusion There is a great need and a challenge to improve cooperation and to create security barriers within our labour units. The most common cause of malpractice is that stated guidelines for fetal surveillance are not followed. Midwives and obstetricians need to improve their shared understanding of how to act in cases of imminent fetal asphyxia and how to choose a timely and optimal mode of delivery.
Litter mixtures often decompose at a different rate than the average of the individual litters, but, so far, the underlying mechanisms are not understood. We propose here an explanation based on a ...model with two litters. The model describes the carbon and nitrogen mineralisation of the litters. The decomposition rates of the litters become linked because the growth efficiency (production-to-assimilation ratio) of the decomposers responds to the amount of inorganic nitrogen (initial plus mineralised) in the surrounding environment. The model shows that, when in a mixture, one litter decomposes always faster and the other one always slower compared to when they decompose on their own. The relative changes in decomposition rates are also equal and consequently the decomposition rate for the whole mixture can be expected to lie between the rates of the two individual litters. The mixture decomposes faster than the average of the two litters separately when the litter of the higher quality also mineralises nitrogen fastest. If the litter of the higher quality instead has the smallest nitrogen mineralisation rate, the mixture decomposes slower. The model predictions are consistent with observations from 23 published experimental litter-mixture studies.
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